/* This file is part of the OWL API.
 * The contents of this file are subject to the LGPL License, Version 3.0.
 * Copyright 2014, The University of Manchester
 * 
 * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License along with this program.  If not, see http://www.gnu.org/licenses/.
 *
 * Alternatively, the contents of this file may be used under the terms of the Apache License, Version 2.0 in which case, the provisions of the Apache License Version 2.0 are applicable instead of those above.
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */
package uk.ac.manchester.owl.owlapi.tutorial.examples;

import static org.semanticweb.owlapi.search.EntitySearcher.getAnnotationObjects;

import java.io.PrintStream;
import javax.annotation.Nonnull;
import org.semanticweb.owlapi.apibinding.OWLManager;
import org.semanticweb.owlapi.model.IRI;
import org.semanticweb.owlapi.model.OWLClass;
import org.semanticweb.owlapi.model.OWLException;
import org.semanticweb.owlapi.model.OWLOntology;
import org.semanticweb.owlapi.model.OWLOntologyManager;
import org.semanticweb.owlapi.reasoner.OWLReasoner;
import org.semanticweb.owlapi.reasoner.OWLReasonerFactory;
import uk.ac.manchester.owl.owlapi.tutorial.LabelExtractor;

/**
 * Simple example. Read an ontology, and display the class hierarchy. May use a reasoner to
 * calculate the hierarchy.
 *
 * @author Sean Bechhofer, The University Of Manchester, Information Management Group
 * @since 2.0.0
 */
public final class SimpleHierarchyExample {

    private static final int INDENT = 4;
    private final OWLReasonerFactory reasonerFactory;
    private final OWLOntology ontology;
    private final PrintStream out;

    private SimpleHierarchyExample(OWLReasonerFactory reasonerFactory, OWLOntology inputOntology) {
        this.reasonerFactory = reasonerFactory;
        ontology = inputOntology;
        out = System.out;
    }

    /**
     * Print the class hierarchy for the given ontology from this class down, assuming this class is
     * at the given level. Makes no attempt to deal sensibly with multiple inheritance.
     */
    private void printHierarchy(OWLClass clazz) {
        OWLReasoner reasoner = reasonerFactory.createNonBufferingReasoner(ontology);
        printHierarchy(reasoner, clazz, 0);
        /* Now print out any unsatisfiable classes */
        ontology.classesInSignature().filter(c -> !reasoner.isSatisfiable(c))
            .forEach(c -> out.println("XXX: " + labelFor(c)));
        reasoner.dispose();
    }

    private String labelFor(OWLClass clazz) {
        /*
         * Use a visitor to extract label annotations
         */
        LabelExtractor le = new LabelExtractor();
        getAnnotationObjects(clazz, ontology).forEach(a -> a.accept(le));
        /* Print out the label if there is one. If not, just use the class URI */
        String result = le.getResult();
        if (result != null) {
            return result;
        }
        return clazz.getIRI().toString();
    }

    /**
     * Print the class hierarchy from this class down, assuming this class is at the given level.
     * Makes no attempt to deal sensibly with multiple inheritance.
     */
    private void printHierarchy(OWLReasoner reasoner, OWLClass clazz, int level) {
        /*
         * Only print satisfiable classes -- otherwise we end up with bottom everywhere
         */
        if (reasoner.isSatisfiable(clazz)) {
            for (int i = 0; i < level * INDENT; i++) {
                out.print(" ");
            }
            out.println(labelFor(clazz));
            /* Find the children and recurse */
            reasoner.getSubClasses(clazz, true).entities().filter(c -> !c.equals(clazz))
                .forEach(c -> printHierarchy(reasoner, c, level + 1));
        }
    }

    public static void main(String[] args) throws Exception {
        String reasonerFactoryClassName = null;
        // We first need to obtain a copy of an
        // OWLOntologyManager, which, as the name
        // suggests, manages a set of ontologies.
        OWLOntologyManager manager = OWLManager.createOWLOntologyManager();
        // We load an ontology from the URI specified
        // on the command line
        String x = args[0];
        System.out.println(x);
        IRI documentIRI = IRI.create(x);
        // Now load the ontology.
        OWLOntology ontology = manager.loadOntologyFromOntologyDocument(documentIRI);
        // Report information about the ontology
        System.out.println("Ontology Loaded...");
        System.out.println("Document IRI: " + documentIRI);
        System.out.println("Ontology : " + ontology.getOntologyID());
        System.out.println("Format      : " + ontology.getFormat());
        // / Create a new SimpleHierarchy object with the given reasoner.
        SimpleHierarchyExample simpleHierarchy =
            new SimpleHierarchyExample((OWLReasonerFactory) Class.forName(reasonerFactoryClassName)
                .getConstructor().newInstance(), ontology);
        // Get Thing
        OWLClass clazz = manager.getOWLDataFactory().getOWLThing();
        System.out.println("Class       : " + clazz);
        // Print the hierarchy below thing
        simpleHierarchy.printHierarchy(clazz);
    }
}
